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Cleveland

Cleveland Cobalt M42 Rectangular Tool Bit 856 5/8 x 7/8 in x 6 in

SKU CH-NMFZ-T0A0A

Cobalt M42 rectangular tool bit for lathe work, 5/8 x 7/8 in x 6 in, non-beveled

  • Cobalt M42 steel resists heat and wear
  • Rectangular 5/8 x 7/8 in cross-section suits lathe tool holders
  • 6 in overall length provides extended reach
  • Right- and left-hand non-beveled design allows versatile grinding
  • Cleveland brand trusted for industrial cutting tools

Cobalt M42 Rectangular Tool Bit

The Cleveland Cobalt M42 rectangular tool bit is a lathe tool blank made from high-speed cobalt steel. It is intended for machinists and metalworkers who need a durable blank for custom grinding of cutting tools. The M42 grade provides enhanced wear resistance for demanding machining applications.

Dimensions and geometry constraints

The blank measures 5/8 inch in overall width, 7/8 inch in overall height, and 6 inches in overall length. Its right-and-left-hand, non-bevelled geometry defines the starting shape, limiting the range of tool profiles that can be ground without additional material removal. These fixed dimensions determine the maximum tool size obtainable from the blank.

M42 cobalt grade

The M42 cobalt composition is the single specification that decides whether this blank suits the workpiece material and cutting conditions. This high-speed steel grade offers superior red hardness and abrasion resistance compared to standard M2 grades, making it the critical factor for high-temperature alloys and heavy cuts.

Highlights

  • Cobalt M42 steel resists heat and wear
  • Rectangular 5/8 x 7/8 in cross-section suits lathe tool holders
  • 6 in overall length provides extended reach
  • Right- and left-hand non-beveled design allows versatile grinding
  • Cleveland brand trusted for industrial cutting tools

Specifications

BrandCLEVELAND

Questions about this item

What does the M42 grade mean for cutting performance?

M42 indicates a cobalt high-speed steel with approximately 8% cobalt content, giving the tool bit higher hot hardness and wear resistance than standard HSS for extended tool life in tough materials.

How does the rectangular 5/8 by 7/8 inch cross-section affect use in a tool holder?

The rectangular blank fits standard tool posts and holders designed for that cross-section, providing a rigid, non-beveled mounting surface for both right-hand and left-hand turning operations.

What does the 856 designation refer to on this tool bit?

The 856 is the manufacturer's style number for this rectangular lathe tool blank, identifying the specific geometry and dimensions of the cobalt M42 blank.

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